The effect of shear flow and dissolved gas diffusion on the cavitation in a submerged journal bearing

Two possible, long standing speculated mechanisms are theoretically investi gated in an attempt to understand previous experimental observations of pre ssure build up in the cavitation zone of a submerged journal bearing. These mechanisms are (I) the shear of the cavity gas bubble by a thin lubricant film dragged through the cavitation zone by the rotating shaft and (2) the mass transfer mechanism which dictates the rare of diffusion of dissolved g as our of and back into the lubricant. A comparison with available experime ntal results reveals that while the cavitation shape is fairly well predict ed by the ''shear'' mechanism, this mechanism is incapable of generating th e level of the experimentally measured pressures, particularly towards the end of the cavitation zone. The "mass transport'' mechanism is found inadeq uate to explain the experimental observations, The effect of this mechanism on the pressure build up in the cavitation zone can be completely ignored.